Starbase 173
From Star Trek: Theurgy Wiki
Starbase 173 was a Federation starbase in operation during the mid-24th century.
When Benjamin Sisko was a sophomore at Starfleet Academy, he performed his field study at this starbase. He was "a little apprehensive" upon arriving, but later came to regard his time there as one of the best experiences of his life. (DS9: "The Ascent")
Thomas Ravon, callsign "Razor" spent his first fifteen years at Starbase 173. He started school at age five.
In 2362 a pre-Academy education program for Starfleet dependents was started at Starbase 173. Thomas Ravon enrolled in this program at the age of fourteen.
In 2363, a medical officer who had served at the starbase for the last fifteen years died in a tragic accident. The officer was the legal guardian of Thomas Ravon. Federation guardians took the boy in ensuring that he could enroll at Starfleet Academy at age seventeen.